a. Technical Field
The instant disclosure relates to elongate medical devices, including steerable elongate medical devices.
b. Background Art
Catheters are used for an ever-growing number of procedures. For example, catheters are used for diagnostic, therapeutic, and ablative procedures, to name just a few examples. Typically, the catheter is manipulated through the patient's vasculature and to the intended site, for example, a site within the patient's heart. The catheter typically carries one or more electrodes, which may be used for ablation, diagnosis, or the like.
To increase the ability to move and navigate a catheter within a patient's body, steerable catheters have been designed. Steerable catheters are often manipulated by selectively tensioning one or more deflection wires running along the length of the catheter, typically offset from a central axis of the catheter, thereby deflecting the distal end of the steerable catheter in one or more directions or planes. These deflection wires are sometimes attached to a metallic catheter component located at the distal end of the catheter, such as one of the electrodes carried on the distal end of the catheter or a pull ring incorporated in the catheter. In other designs, the deflection wires are embedded in a portion of the distal end of the catheter or otherwise attached to the distal end.
Once the catheter has been positioned at the target site, it often becomes necessary for the catheter to assume a particular shape in order to perform its desired function (e.g., a particular curvature size or radius). Further, it may be desirable for a catheter to be capable of being deflected into multiple shapes.
One known multi-shape elongate medical device includes multiple pull rings, each attached to a different longitudinal portion of the catheter shaft. Each pull ring may be coupled to one or more deflection wires for movement in one or more planes. Examples of such a medical device are shown in U.S. patent application Ser. No. 12/347,100 (issued as U.S. Pat. No. 8,123,721) and U.S. patent application Ser. No. 13/406,152 (published as U.S. patent application publication no. US 2012/0203169 A1), both of which are hereby incorporated by reference in their entireties as though fully set forth herein.
The foregoing discussion is intended only to illustrate the present field and should not be taken as a disavowal of claim scope.